Safety device for rocket steered projectiles



5 Sheets-Sheet 1 25 W lfa I w FUZE N. CZAJKOWSKI SAFETY DEVICE FOR ROCKET STEERED PROJECTILES Filed June 19. 1956 Sept. 26, 1961 Sept. 26, 1961 N. CZAJKOWSKI SAFETY DEVICE FOR ROCKET STEERED PROJECTILES Filed June 19. 1956 3 Sheets-Sheet 2 INVENTOR N. CZAJKOWSKI BY W0.

ATTORN Y5 Sept. 26, 1961 N. CZAJKOWSKI 3,001,478

SAFETY DEVICE FOR ROCKET STEERED PROJECTILES 3 Sheets- Sheet 3 Filed June 19. 1956 E w V M255 :35 545mm Z 335m $.52 m2m 1356 $33; 559. m

5&2: S25 MNE WUE ATTORNEYS 3,001,478 SAFETY DEVICE FOR ROCKET STEERED PROJECTILES Norman Czajlrowski, Chevy Chase, Md.', assignor to the United States of America as represented by the Secretary of the Navy Filed June 19, 1956, Ser. No. 592,470 6 Claims. (Cl. 102-702) (Granted under Title 35, US. Code (1952), sec. 266) The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

The present invention relates to a projectile fuze and more particularly to a new and improved safety system for use in a proximity fuze of the type employed in a rocket steered projectile.

Accordingly, the invention contemplates the provision of a novel safety system for a fuzed projectile wherein means are provided for preventing arming of the fuze FIG. 8 is a pictorial view illustrating the sequence of operation ofthe system of'FIG. 1.

Referring now to the drawings wherein like reference characters designate like parts throughout the several views and more particularly to FIG. 1, the numeral 10 generally indicates the safety system constructed in acuntil the projectile has been fired from a gun and traveled a predetermined distance from the muzzle thereof, and in which means controlled by the movement of an explosive actuated arming rotor unshorts and electroresponsive primer and renders a firing circuit effective whereupon the primer is fired by a conventional proximity fuze when the projectile comes into proximate relation with respect to a target and which unshorts and initiates a time delay or self-destruction device thereby to fire the primer by way of the proximity fuze in the event that the firing signal is not received by the fuze.

An object of the present invention is to provide a new and improved safety system for rocket steered projectiles.

Another object of the invention is the provision of a safety system for arming the fuze of a rocket steered projectile a predetermined period of time after the projectile has been fired from a gun.

Still another object of the invention is the provision of an improved fuze for a rocket steered projectile in which a normally shorted firing circuit and a normally shorted time delay circuit are unshorted after the projectile has been fired from a gun and when the projectile is subjected to lateral acceleration resulting from the initial blast of the rocket motor as the projectile is propelled and steered along its trajectory.

A still further object of the invention is the provision of an improved fuze for a rocket steered projectile wherein means actuated in response to lateral acceleration of the projectile renders the fuze effective to initiate an electrical primer and explode the projectile when the projectile is in proximate relation with respect to a target or in time delayed relation with respect to the initiation of a delay device in the event that the fuzed projectile fails to come within signal receiving range of the target.

Other objects and many of the attended advantages of this invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with cordance with the present invention and comprising a conventional proximity firing apparatus and self-destruction timing apparatus shown in block form and indicated by the reference characters 11-12 respectively. A suitable lateral acceleration switch 13 is included in the system, the switch being similar to the device disclosed and claimed in the copending application of Audley B. Leaman et al., for a Lateral Acceleration Switch, Serial No. 296,777, filed July 1, 1952, now Patent No. 2,980,- 773. The system further provides an arming mechanism including an arming rotor shown in dashed outline as at 14, a pair of fuze wires 15-16, a time delay electroresponsive primer 17, a normally inactive reserve energizer battery BA, and an initiating or firing electroresponsive primer 18. It will be noted that primer 1% and timing apparatus 12 are normally shorted by their respective fuze Wires 15-16 and switch 13 is normally locked and grounded. By this arrangement the system is maintained in a safe condition until the projectile has been fired from a gun and traveled a predetermined distance from the muzzle of the gun and subjected to lateral acceleration. The operation and structural arrangement of the system will be more clearly apparent as the description proceeds.

Referring now to FIG. 2 the arming mechanism comprises a terminal block 19, a primer housing 21, a rotor housing 22 and a cover plate 2'3, the aforesaid elements being secured together in any suitable manner such, for example, as by screws. The housing 22 and components parts thereof, FIG. 5, are similar to the device disclosed and claimed in the copending application of Charles F. Bild for Arming Locking Device for a Fuze, Serial No. 267,903, filed January 23, 1952, now Patent No. 2,969,- 737. The arming rotor 14 is rotatably mounted as at 25 and normally locked in an initial safe-position by rea- 22 in communication with pressure chamber 33 the purpose of which will become more clearly apparent as the description proceeds.

The housing 21 is provided with a recess 34, FIGS. 4 and 6, for receiving the firing primer 18 and having a terminal block 35 secured thereto as at 36, the block supporting the aforesaid fuze wires 15-16 in the path of travel of the pin 32 and adapted to be broken by the pin as the rotor 14 is moved from an initial safe position to an armed locked position. Housings 21 and 22 are provided with corresponding openings 37 for receiving the delayprimer '17 and corresponding openings 38 for receiving the aforesaid late-ral'acceleration switch 13.

As more clearly shown in FIG. 1, the switch 13 is adapted to be actuated in response to setback and lateral forces and comprises an annular contact 41 and a vibraing sleeve 43 carried by a movable piston 44, the piston carrying a pair of contacts 45 normally in engagement with the annular contact 41 and thus by this arrangement the switch is maintained in a safe condition until the projectile is fired from a gun and subjected to lateral acceleration resulting from the initial blast from the rocket motor as the projectile is steered along its trajectory.

For a more complete understanding of the operation of the safety system attention is directed to FIGS. 1 and 7, whereupon as the projectile is fired from a gun the release mechanism 29, FIG. 7, is actuated to a release position in response to setback force thereby releasing the arming rotor 14 for rotation from an initial safe position to an armed position and concurrently therewith setback force actuates plunger 44 an amount sufficient to move sleeve 43 out of engagement with the vibratory contact 42. and contacts 45 out of engagement with the annular contact 41 thereby removing the ground from annular contact 41 and releasing the vibratory contact for lateral movement, whereupon the switch is rendered efiective to be operated in response to lateral forces applied thereto, resulting from a sudden change in the course of the projectile as the rocket motor is initiated. In response to such forces the vibratory contact 42 moves into engagement with annular contact 41 whereupon a firing impulse is supplied to delay primer 17 from battery B by way of contacts 41-42, conductor 46, primer, and thence to ground. The delay primer 17 is constructed and arranged to permit transient vibration of the projectile to subside before a black powder gas producing charge is ignited thereby, the delay being substantially 0.20 second. As the black powder charge is ignited and burns, the gases generated thereby enter chamber 33 and When the pressure in chamber 33 reaches a predetermined value the piston 26 is forcibly driven forwardly, thereby moving the rotor 14 from an initial safe position to an armed locked position. As the rotor moves to the armed position, fuze wires 15 16 are broken by pin 32 thereby unshorting the primer 18 and timing apparatus 12. In the armed condition, detonator 31 carried by the rotor aligns with primer 18 and leadin charge 46 carried by member 22 as more clearly shown on FIG. 6.

As the fuze wires 15 and 16 are broken, a firing circuit is established between the firing apparatus and primer 18 by way of conductors 4748 and concurrently therewith an initiating circuit is established between normally inactive battery BA and the timing apparatus 12 by way of conductors 4951 whereupon the apparatus is initiated. When this occurs the system is fully armed and thus should the projectile come sufficiently close to the target to receive a reflected electromagnetic wave signal there from, the proximity apparatus 11 is initiated. Upon initiation of the apparatus 11 primer 18 is fired thereby and the projectile is exploded on or near the target. Should the proximity apparatus fail to be initiated in the aforesaid manner, it will be understood that the self-destruction timing apparatus 12 will function a predetermined period of time after it has been set in operation and initiate the apparatus 11 by way of conductors -253 and thus as apparatus 11 is initiated, primer 18 is fired thereby by way of conductors 4-7-48.

For a more complete understanding of the operational sequence of the safety system attention is directed to FIG. 8 wherein the successive cycles of operation of the system is illustrated in pictorial form from the time the projectile is fired and propelled along its trajectory until the timing apparatus functions to explode the projectile should the proximity firing apparatus 11 fail to receive an initiating signal from a target.

In view of the foregoing, it will be apparent that a new and improved safety fuze system has been devised for a rocket steered projectile wherein means are provided for maintaining the fuze system in an initial safe condition during handling and transportation and until the projectile has been fired from a gun and subjected to lateral acceleration after travelling a predetermined distance from the muzzle of the gun whereupon means actuated in response to lateral acceleration initiates arming of the system and renders the system effective to explode the projectile when the projectile is in proximate spaced relation with respect to a target or in time delayed relation with respect to the initiation of a timing device in the event that the proximity apparatus fails to come within signal receiving range of the target.

Obviously many modifications and variations of the present invention are possible in the light of the above teachings. It is therefore to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.

What is claimed as new and desired to be secured by Letter Patent in the United States is:

1. In a safety fuze system for an explosive rocket steered projectile, a normally shorted firing circuit and a normally shorted timing circuit, means movable in response to an explosive force-for unshorting said circuits, explosive means for applying said force to said movable means as the explosive means is fired, means including a device operatively connected to said explosive means and actuated in response to lateral acceleration of the projectile resulting from an initial rocket blast as the projectile is steered along its trajectory for firing said explosive means, a firing apparatus included in said firing circuit and initiated when said projectile is in proximate spaced relation with respect to a target for exploding said projectile, a timing device included in said timing circuit, means included in said timing circuit for initiating said timing device as said timing circuit is unshorted, said timing device being operatively connected to said firing apparatus for initiating the firing apparatus a predetermined period of time after initiation of the timing device.

2. In a safety fuze system for an explosive rocket steered projectile, a normally shorted firing circuit and a normally shorted timing circuit, an arming member movable in response to an explosive force for unshorting said circuits, a time delay pyrotechnic element for applying said force to said arming member a predetermined period of time after said delay element has been initiated, means including a vibratory contact for initiating said time delay element as said contact is vibrated in response to lateral acceleration of the projectile as the projectile is steered by an initial rocket blast, an electroresponsive primer included in said firing circuit and rendered operable as the firing circuit unshorted, means included in said firing circuit and initiated when said projectile is in proximate spaced relation with respect to a target for firing said primer and thereby explode said projectile, timing means included in said timing circuit and means included in said timing circuit for initiating said timing means as the timing circuit is unshorted, said timing means being operatively connected to said firing means for initiating the firing means a predetermined period of time after initiation of the timing means.

3. In a safety fuze system for an explosive rocket steered projectile, a normally shorted firing circuit and a normally shorted timing circuit, an arming member movable in response to an explosive force for unshorting said circuits, a time delay pyrotechnic element for applying said force to said arming member a predetermined period of time after said delay element has been initiated, means including a vibratory contact for initiating said time delay element as said contact is vibrated in response to lateral acceleration of the projectile as the projectile is steered by an initial rocket blast, an clectroresponsive primer included in said firing circuit and rendered operable as the firing circuit is unsho-rted, firing means included in said firing circuit, timing means operatively connected to said firing means for initiating said firing means and firing s id primer when a prcd ennincd period of time has elapsed, and means included in said timing circuit for initiating said timing means as said timing circuit is unshorted.

4. In a safety fuze system for an explosive rocket steered projectile, a normally locked explosive actuated device, means responsive to an inertial force for locking said device, said locking means being actuated by setback force to release said device as the projectile is fired from a gun, a normally locked impulse switch actuated to a release position in response to said force, an arming rotor locked to said device in an initial safe position, means on said arming rotor in engagement with said device for moving said arming rotor from said initial safe position to an armed position as the device is moved by an explosive force applied thereto, a time delay pyrotechnic element fired in response to an electrical impulse received thereby for applying said force to the device when a predetermined period of time has elapsed, means including a vibratory contact carried by said impulse switch for supplying said impulse to said time delay element as the contact is vibrated in response to lateral acceleration as the projectile is steered in response to an initial rocket blast, a firing circuit including a normally shorted electroresponsive primer, a normally shorted timing device, means on said arming rotor for unshorting said primer and said timing device as the arming rotor is moved from said initial safe position to said arm position, and means operatively connected to said timing device and initiated thereby when a predetermined period of time has elapsed for firing said primer thereby to explode said projectile.

5. In a safety fuze system for an explosive rocket steered projectile, a normally locked explosive actuated plunger, means including an inertia responsive device for locking said plunger and adapted to be actuated by setback force to release said plunger as the projectile is fired from a gun, a normally locked impulse switch actuated to a release position by said force, an arming rotor locked to said plunger in an initial safe position, means on said rotor in engagement with said plunger for moving the rotor from said initial safe position to an armed position as the plunger is actuated in response to an explosive force applied thereto, a time delay pyrotechnic element responsive to an electrical impulse for supplying said force to the plunger when a predetermined period has elapsed, means including a contact carried by said impulse switch for applying said impulse to the delay ele-- ment as said contact is vibrated in response to lateral acceleration of the projectile in response to a steering explosion, a firing circuit including a normally shorted electroresponsive primer, an initiating circuit, fuze means for shorting said primer and said initiating circuit and adapted to unshort said primer and said initiating circuit as the fuze means are broken, means carried by said rotor for breaking said fuze means as the rotor is moved from 'said initial safe position to said armed position, and means included in said circuits and rendered effective as said fuze means are broken for firing said primer.

6. In an explosive steered projectile, in combination, a normally locked explosive actuated device, means responsive to an inertial force for locking said device and adapted to be actuated by setback force to release said device as the projectile is fired from a gun, a normally locked switch actuated to a release position in response to said force, arming means locked to said device in an initiated by said timing device a predetermined period of initial safe position, means on said arming means in engagement with said device for moving said arming means from said initial safe position to an armed position as said device is actuated in response to an explosive force applied thereto, a time delay pyrotechnic means for supplying said force to said device a predetermined period of time after said time delay means has been fired, means including a vibratory contact carried by said switch for firing said time delay means as said contact is vibrated in response to lateral acceleration of the projectile in response to a steering explosion, a normally shorted electime after said timing device has been set'in operation.

References Cited in the file of this patent UNITED STATES PATENTS 913,524 Leon Feb. 23, 1909 1,133,183 Reineke Mar. 23, 1915 2,737,890 Brode Mar. 13, 1956 2,775,942 Dell Ian. 1, 1957 

